Debian Security Advisory

DLA-2786-1 nghttp2 -- LTS security update

Date Reported:
16 Oct 2021
Affected Packages:
Security database references:
In Mitre's CVE dictionary: CVE-2018-1000168, CVE-2020-11080.
More information:

Two security issue have been discovered in nghttp2: server, proxy and client implementing HTTP/2.

  • CVE-2018-1000168

    An Improper Input Validation CWE-20 vulnerability found in ALTSVC frame handling that can result in segmentation fault leading to denial of service. This attack appears to be exploitable via network client.

  • CVE-2020-11080

    The overly large HTTP/2 SETTINGS frame payload causes denial of service. The proof of concept attack involves a malicious client constructing a SETTINGS frame with a length of 14,400 bytes (2400 individual settings entries) over and over again. The attack causes the CPU to spike at 100%.

For Debian 9 stretch, these problems have been fixed in version 1.18.1-1+deb9u2.

We recommend that you upgrade your nghttp2 packages.

For the detailed security status of nghttp2 please refer to its security tracker page at:

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: